No abstract

The main target of the present work is to screen three tested strains of Lactobacillus spp. for functional characteristics for probiotics. The potential probiotic characteristics of three Lactobacillus spp. strains were studied with regard to acid / bile tolerance and surviving in gastric / intestinal juices. Results obtained revealed that all tested lactobacilli strains showed much greater stability at different low pH values (1.5, 2 and 3), and normal growth at bile concentrations up to 1 % w/v, which recommended these cultures to use as probiotic bacteria. Moreover, data obtained declared that all tested Lactobacillus cultures were considered intrinsically tolerant to gastric and intestinal juices. The potential role of these probiotic Lactobacillus cultures on serum lipid of rats was studied. Twenty-five male albino rats were randomly and equally divided into five groups, five rats each. After an adaptation period of 7 days, the first group was fed on basal diet served as control I, the second group was offered basal diet + buffalo's milk plus one of the tested lactobacilli strains. At the end of the 28 days' experimental period, the rats were killed. However, blood samples were collected at the beginning and the end of experiment. From results obtained it could be concluded that supplementation of diets with fermented milk culture with either L. casei or L. rhamnosus resulted in noticeable decreases in total cholesterol, LDL-cholesterol and triglyceride contents. Moreover, heoretic indexes 1, 2 and l LDL/HDL ratio were markedly reduced in rats received fermented milk as compared with control treatment I (dry diet). In conclusion, fermented milk can decrease in the faecal counts of either coliform or streptococci.